


Why To Keep A Promise

by Aoaka_chan



Category: Free!
Genre: Idk what happened, M/M, Plot What Plot/Porn Without Plot, Punishment, Spanking, This was supposed to be a drabble, Toys, oh well ...
Language: English
Status: Completed
Published: 2018-03-20
Updated: 2018-04-25
Packaged: 2019-04-05 04:58:43
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,361
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14036679
Author URL: https://archiveofourown.org/users/Aoaka_chan/pseuds/Aoaka_chan
Summary: Don't make a promise to someone if you can't keep it, or there will be consequences.Or at least that's what Haru had learned from experience.





	1. Chapter 1

**Author's Note:**

> Ok, so this was supposed to be a short fic on spanking, but then I went to the discord nsfw chat and well ...   
> this happened, I hope you'll enjoy it nonetheless

 

_“Don't eat mackerel the whole time! You need to keep a healthy diet."_

_"Fine."_

_"Promise?"_

_" ...  Fine."_

_“Fine?”_

_Haru grumbled under his breath._

_“I promise.”_

_“Good boy”_

....  


That was there 'emotional' goodbye at the airport, Rin was heading to Australia to take care of some paperwork or something, Haru didn't really know, he was a little upset that Rin was leaving, but what mattered to him anyway was that Rin is coming back in two weeks, he can take that much at least.

And he really _really_ tried to keep his promise to Rin and eat something besides salt-grilled mackerel, but all of his efforts were to no avail.

It was like all of the food just disappeared from land, he would stand in the convenient store, staring at all the products, but none of them looked edible.

So he somehow ended up buying mackerel every single time.

What's worse than that, was that he lied through his teeth when Rin asked if he was keeping his promise.

And now two weeks later, two weeks of three times a day mackerel.

Rin was coming back.

Haru had practice in the evening, so he couldn't meet Rin at the airport, they were meeting in their apartment instead, he didn't know whether he should tell Rin the truth or not, he didn't want to lie to him, but he kinda already did? so what to do? Admit the whole thing and risk disappointing Rin, or just not tell him at al-

His thoughts were cut short by a jiggling sound in the Keyhole, he stood up abruptly and walked hurriedly to the door to meet Rin.

The door opened and he was engulfed in a tight hug from the red-haired.

"I'm home, Haru." said Rin against his ear. Haru buried his face in Rin's neck and whispered back, "welcome home."

Rin's arms tightened around him for a second before pulling back, locking eyes with dark blue eyes and leaning slowly to kiss him, Haru made a small humming noise in the back of his throat, and closed his eyes as leaned into the kiss, happy to feel Rin against him again, to feel his hands massaging his hips slowly, sensually.

 They stayed like this for a few moments before Rin pulled back from the kiss and locked eyes with him again.

"So," he said, "did you manage to keep our promise?"

Haru hesitated a bit, not Knowing what to say, so he opted to give Rin another kiss, Rin kissed him back for a couple of seconds, before pulling back again and staring at Haru waiting for an answer.

"And..?"

"Well ... " Haru went silent, it was that much harder to lie to Rin to his face, he looked at the side, trying to make his brain work properly so he can come up with something.

"I know you only ate mackerel the whole time," Rin said with a somehow serious voice.

Haru looked at him with a little panic, "H-How did you?"

"You know, people talk, Haru," Rin smirked, "Sousuke asked Makoto how were you holding up, and Makoto told him you were doing a 'mackerel-strike' while I was away," he then leaned to kiss his cheek softly, although Haru could feel that there was something not right, that soft kiss making his stomach twist oddly.

"And you know how Sousuke have been dating my sister, so ... You can guess the rest."

Haru didn't know what to say, he opened his mouth, but nothing came out, he just stared at Rin's eyes, how calm they looked, like nothing happened.

"You are not mad?"

Rin chuckled but his eyes weren't laughing.

 "Oh no, I'm mad alright, you didn't just break our promise, but you lied about it several times as well,"

Haru broke eye contact to look aside because Rin's gaze was too much for him now, he felt his cheeks heating with shame and embarrassment.

"Oh, so we are blushing now, aren't we?" he tightened his hands on Haru's hips and leaned so his lips were touching his ears.

"I'm going to give you something to blush about."

 Haru, startled by the low whisper near his ear, looked at Rin with confused blue eyes.

"Huh?"

Rin caressed his cheek with his thumb, speaking softly like he was telling Haru how much he loved him.

"Well you know, breaking a promise and lying to your boyfriend are really bad things to do,"

Haru was feeling embarrassed by what he has done, but somehow, being scolded by Rin like this, combined with the soft touches of his boyfriend and the fact that he didn't see him for two weeks, were waking some weird ... excitement? Maybe anticipation? deep within him.

"And bad boys should be punished."

Rin followed his words with a kiss on his cheek before taking his hand and leading him to their bedroom, Haru didn't Know what Rin meant by punishment, but since they were heading to the bedroom, he kinda knew what to expect.

Once they were there, Rin put down his back bag -which Haru just noticed that he was still carrying- on the floor and started going throw it, he tried not to fidget in his place, trying to calm his racing heart, before Rin took out a small black case and he threw it on the bed, he sat beside it, took both of his hands and guided him to stand right in front of him, and without saying a word, he started loosening his belt, Haru jumped a little and put his hands on top of Rin's, in an attempt to stop him.

"W-What are you doing?" Haru said, not understanding how a blowjob was a punishment, plus, Rin's actions were starting to worry him a bit.

"I told you that bad boys should be punished"

"But ..." Haru mumbled still gripping Rin's hands with his own, when Rin looked meaningfully at his hands in a way that obviously said ‘ _take them off_ ’, for some reason Haru's hands fell to his sides, something about Rin's behavior, about his looks, even the aurora he was emitting, was bringing up a side in him, he didn't even know he had.

Rin finished unzipping his pants, and pulled them down with his underwear in one swift move, Haru could swear his face was on fire, as his crotch was lined up with Rin's face, -he was really thankful that he decided to wear one of Rin's T-shirts today, as it was a little bit longer than his own, and covered a good deal of his dick- but instead of leaning in, Rin sat back and made himself comfortable on the bed, he looked at Haru expectedly, but Haru didn't know what he was supposed to do, sensing Haru's confusion, Rin sighed before batting his lap, "Come on, lay across my lap"

 _Across?_ Haru got confused for a minute, why across? That way he wouldn't be ...

He felt his heart sink as it clicked in his mind, Rin wasn't going to punish him in a sexy kinda way, like they usually do, but he was going to actually punish him ... to spank him!

"Ah, I see you finally realized what your punishment is." Rin said with a hint of a smirk playing on his lips.

"We can't do that!!" Haru almost yelled,

Not believing what Rin was saying.

"And why not?" Rin asked, lifting his eyebrow.

"Because it's ... it's ... because I'm ... and you..." Haru couldn't come up with anything comprehensible, his brain being shut down at the very idea of Rin spanking him.

Rin sighed, "You make a good point, but you're still going to be punished, are you gonna come here or am I going to have to drag you here myself?"

He didn't look like he was joking.

"But I ... " Hare couldn't find it within himself to do it, just walking there, laying on Rin's lap, waiting to be spanked, hell he had a hard time just believing that Rin was actually going to do that, when Haru didn't move and just kept looking at Rin with an unbelieving, panicked expression, Rin grabbed his hand and jerked him forward so he stumbled a little, trying to not fall down, but Rin's hand kept pulling him until he lost his balance and fell right on him, Rin made a quick job of moving Haru until he lied across his lab, with his ass sticking out over his knees.

"Rin!" Haru said panicking and embarrassed at his current position, he squirmed, trying to stand up, but Rin's hands were pressing between his shoulder blades to keep him down, one of his legs hooked over the back of his knees, so no matter how Haru tried to get away he couldn't.

"Sit still or your spanking will be harder than planned" Rin said with a somehow cold voice, effectively making Haru stop squirming, he was now hyperaware of his naked ass sticking in the chilly air of the room, how Rin's hand was now caressing his cheeks softly, he was sure his face would rival Rin's hair in color.

"So, do you know why you're being punished?"

_Oh my god, Rin wants him to talk now!_

He stubbornly refused to talk, trying to hold on to what was left of his pride, he will no-

S _mack_

"Ah!" Haru yelped in surprise, his body jerking forward from the hard slap as he started feeling a little sting on his right cheek.

"Answer me, Haru"

"I ..." he swallowed, trying to compose himself, "I broke our promise," he said in a low voice.

"And?" Rin insisted.

God, when this was over, Rin is going to regret this.

"And I lied" he mumbled again.

"Good," Rin said, back to caressing his cheeks, "now that you know, your punishment is going to be a 10 Minutes spanking, and a minute in between for a break, ok?"

Haru nodded, fisting the sheets, he just wanted this to be over as quick as possible.

And without further delay, Rin started slapping his butt cheeks, the first couple of slaps surprised him a little, but then he got used to Rin's hand being brought down harshly on his bare butt, he bites his lower lip hard so no voice whatsoever will escape his throat, he clenched his cheeks as they grew sensitive, every slap hurting more than the one before.

After a couple of minutes of hard slaps, which felt like forever to Haru, he was suddenly aware of his erection, his dick was harder than it should be while getting a spanking.

Was this turning him on? Was getting spanked really turning him on?

He was now conscious of the way Rin had an arm slung around his waist to keep him in place, how his thumb was making soft circles on his hip, contrary to the way he was delivering his slaps with the other hand, Haru felt exposed, embarrassed, dominated and to his complete horror it was turning him on more than anything, being under Rin's mercy, laying across his lap, getting spanked like a bad little boy, the delicious sting he felt every time Rin brought his hand down.

_Delicious?_

_Oh god_ …

Haru buried his face in the sheets, embarrassed by his own thoughts, now biting his lips to keep himself from moaning out, god if Rin noticed, he woul-

The slaps stopped, Haru let out a shuddering breath, noticing his eyes were a bit wet, noticing how hot his butt felt, he guessed it was time for the break Rin was talking about.

"Oh, what's this?" Rin said, a hint of smugness in his voice, and Haru noticed Rin's thigh pressing against his erection.

"Well well, someone is enjoying their spanking a bit too much"

That's it, that was how Haru is going to die.

"I was planning on using this after we were done here, but ... change of plans"

 _Using what?_ Haru wanted to ask, but couldn't find his voice to do it.

He heard Rin fumbling, with the black case, he guessed, a bottle opened and before he knew it, two slick fingers made their way between his butt cheeks, massaging his entrance but not pushing in, he couldn't help the quiet moan that escaped him, the fingers going past his crack, massaging behind his ball, before going back up as Rin started pushing one of his fingers in.

"Mnh .. " Haru whimpered lightly.

"So tight," Rin said, sounding a bit breathless, "didn't you touch yourself while I was gone?"

Haru shook his head, still not finding his voice, groaning as Rin pushed a second finger, maybe too soon, but damn if he wasn't enjoying the sting that came with it.

Pumping his fingers a few times, Rin took them out, Haru merely bite down a whine, then he heard more fumbling before he felt Rin's hands spread his butt cheeks and something that wasn't his finger being inserted into his ass, he jerked, trying to turn around to see what Rin was doing, but a slap on his butt made him stop.

"Stay still," Rin said, pushing the oval object till it was as deep as it can go inside him.

"Now lift your hips a bit" Rin ordered.

Haru weakly supported his feet on the ground, lifting himself a bit, sighing when his erection got a little more free space, another sigh escaped his lips as Rin's hand found its way around his hips and then to his cock, giving it a few stocks.

"Look how wet you are Haru, who knew you had a spanking kink" Rin commented way too smug for his taste, and although he wanted to deny it, say that, no, he didn't have a spanking kink, but it was too obvious that he enjoyed this, a small voice in his head scoffed at the idea of denying it, so he stayed silent, enjoying the slow tugs, until something hard grabbed the base of his cock tightly.

"Rin!"

"Yeah?" He answered so innocently, Haru wanted to hit him, he turned his head to glare at his boyfriend.

Rin met his eyes calmly, back to stroking his dick.

"Oh, this? This is a cock ring, it won't let you cum until I say so" his hand then stopped stroking and moved away, "and this here ...", A loud moan ripped itself from his throat as the small object in his ass started vibrating, "I think you figured it out yourself".

Haru was back to burying his face in the sheets, trying to muffle his voice.

"Now let's get back to business"

As Rin started to spank him again, he just couldn't keep his voice down anymore, because every time he was slapped, be would reflexively clench his butt, resulting to tighten around the vibrator, which was conveniently located directly at his prostate, but if he didn't clinch it the slap would hurt even more.

"Ah! Rin!" Haru plead, he wanted Rin to stop, he was overwhelmed by the sensations coming from all over his body, it was just too much, the hard slaps, the vibration, the tightness around his cock, he felt his eyes tearing up.

"Three more minutes Haru" Rin was back to stroking the side of his hip, in what Haru assumed to be a comforting gesture, but wasn't.

He tried his hardest to stop squirming, but couldn't, the three minutes feeling like a lifetime.

"AAH" an embarrassingly loud scream ripped through him, as Rin's hand moved to spank the flesh between his ass and thighs, which apparently was more sensitive, he felt tears making their way down his cheeks, as it hurt, but felt so good he was getting dizzy.

"Rin! Stop!" He whimpered, trying to get away, he just couldn't take it anymore, but the vice grip Rin had on him wasn't going to let him go anytime soon.

Haru panted as the muffled moans and groans kept escaping his lips, Rin kept hitting that sensitive spot, again and again and the strong vibration deep inside him wasn't helping, he didn't know if it was pleasure or pain he felt, too many sensations turning his brain into mush, he couldn't control the loud sounds he made every time Rin's hand landed on his butt.

"P-Please..." he whispered, and Rin's hand stopped moving, Haru knew that his pleading tone and the word ‘please’ were what made his boyfriend stop, as Haru didn't use them, and he never thought he would.

Rin caressed his butt lightly with his fingers feeling how warm it felt to the touch, and Haru knew if only he can make eye contact with Rin, if only Rin would look at his eyes, it would be done, cause he knew exactly what his eyes did to Rin, he knew that with one look, Rin would be at his mercy and not the other way around, so he turned his head to the side, trying to catch Rin's eyes, he saw Rin staring at his butt fixedly, as if he was fascinated by it, Haru wanted to snort.

"Rin ... " he called softy, and that did the trick, Rin turned to him and locked eyes with Haru, he saw the ruby eyes widening a bit, and he froze, exactly what Haru wanted, with Rin's grip not so tight anymore, he wiggled and noted the embarrassing wet spot he left on the other's jeans, he sat up, just to straddle Rin's lap, resting his arms at his shoulders, looking directly at the black blown eyes, what Haru didn't understand though was the worried look on Rin's face, until Rin left up his hands to his face, whipping away the tear tracks and caressing his face gently.

"Are you ok?" Rin asked, and Haru couldn't help but nuzzle the hand on his cheek, Rin's hand slide down to hug him around his waist, tugging him closer to his body, Haru let out a moan, the movement causing the vibrator to shift inside him, pressing against his prostate yet again, his hips jerking forward, and he was suddenly reminded how painfully hard he was.

"C'mere," Rin said tugging Haru closer for a passionate kiss, Haru kissing back just as furiously, not knowing he wanted to kiss Rin so badly until just now, he gripped Rin's hair tightly and pushed his tongue in the wet heat, shuddering when Rin sucked on it.

"Mngh!!" Haru groaned into his lover's mouth as he felt Rin's hands slide down to his red butt, squeezing it and playing with the wire of the vibrator, making it move inside him, before starting to tug it out, slowly until it popped out of him, He let a sigh of relief as nothing was stimulating his prostate anymore, but his relief didn't last, when two of Rin's fingers found their way to his entrance, pushing in fast and deep, making him break the kiss in surprise, Rin tugging him close again, this time pushing his tongue into Haru's mouth, Haru's heart thumbing faster when Rin hastily added a third finger.

"Shit Haru, I wish you can see how hot you look now" Rin groaned loudly, leaning close to his ear, "I just want to rip your little ass apart"

Haru couldn't help the shiver, because he too wanted Rin to be inside him, to fuck him as hard as he can and let him cum so hard, to make him forget not seeing his boyfriend for two weeks.

"I see you like that idea too," Rin smirked, "Come on, you know what to do".

Haru glared at his lover, trying to convey that he was not pleased with Rin's tone, but with the neediness he felt, and his cock straining against the ring, he decided to suck it up, and moved his hands lower, undoing Rin's button and zipper, before tugging his pants and underwear to his knees -with Rin's help- after he was done with the clothes, Haru quickly poured some lupe on his fingers before grabbing Rin's dick to slick it, not bothering to warm up the lupe a bit first, which earned him a glare and a hard squeeze on his ass, making him hiss as fuck was his butt sensitive after the thrashing it got.

Haru made a quick job of lupping his lover, a few tugs before he lift himself a little and reached behind him to line Rin's dick with his hole, sinking in slowly, groaning at the stretch and the feeling of Rin filling him, hearing Rin moaning and holding his hips tightly, though not pushing him down, which Haru appreciate, he paused when Rin was half way in, needing to catch his breath, Rin whispered his name and rested their foreheads together, kissing the tip of his nose lightly, making his heart flutter at the soft gesture.

After a few seconds, Haru continued to push himself down until he was completely sitting on Rin's thighs, hands going up to tangle with the red locks, pulling Rib in for a soft kiss, the tenderness of it making his heart go on a frenzy.

When he adjusted a bit better, he started lifting himself and dropping, going faster every thrust until he sat a quick base, the position making Rin go so deep inside him, it was maddening, Rin’s mouth attacking his neck with bit’s and licks, but after a few seconds of hard thrusts, Haru felt the familiar coil, the need to come, but he couldn't just yet, he couldn't with the damn ring gripping around his cock so tightly it was impossible to cum, just making him stay at the edge, were it was so good but the need to release is also unbearable.

"Rin, mnngh" He couldn't help the needy moan that came out, he couldn't move anymore, his legs shaking from the overwhelming pleasure, "Rin, I can't.."

He said between hard breaths, Rin eyes widening as he understood why Haruka had stopped.

"You're gonna be the death of Nanase" Rin said in a hoarse voice, gripping his waist tightly before flipping them over, so he laid on his back, Rin between his legs, he moved close to Haru's ear, licking it and whispering hotly, "I'm gonna fuck you senseless, Haru".

Haru moaned loudly as Rin sat back, gripping the back of his thighs, pushing them up and apart before thrusting in him so fast it made him see stars, he sat a hard, fast base, quickly angling to push against the spot that he knew would drive him insane, there was no stopping his moans now, loud and needy, filling the room, he was so ready to come now, he was ready for a while but that damn ring won't let him, and the sexy basterd fucking is brain out won't take it off, he didn't even have the mind to be embarrassed about being so obscenely spread on the bed, his legs in the air, as he only could think about the person in above him now.

"Rin, I ... I need to .. too muc-AHH!" He screamed on a particular, hard, well-aimed thrust.

"Shit!" Rin cursed loudly and for the first time this night, Haru looked at Rin with pleasure dazed eyes, taking in his boyfriend, Rin's face was red with excursion, sweating and panting loudly, eyes completely black, and Haru can safely say he never saw Rin so turned on before, and this somehow turned Haru on even more, making his release that much more necessary.

"Rin, take it off" he panted, his body shivering in need.

"Ask nicely"

It's official now, Haru officially hated his boyfriend.

"Rin!"  Haru tried to say in a warning tone but came out as a choked gasp.

Rin didn't answer him, just continued driving in him like a madman and soon Haru was running out of options.

He just doesn't care anymore.

"Please… Rin," Haru said, "let me cum." he added just to make sure.

Rin cursed again, before slowing down to take off the ring, Haru heard a click and the pressure was off his cock, he wanted to sigh in relief but got chocked half way when Rin started fucking him harder than before if it's possible, with no ring to hold his orgasm back, it only took a couple of hard thrusts against his prostate, and his back was arching, white ropes landed on his stomach, sending him into the most intense orgasm he had ever had until now.

When he was back to earth again, he felt Rin -in out of body sort of way- cum inside him, slowly jerking his hips a few time to ride it out, until he pulled out and collapsed on his side beside Haru.

They laid there trying to catch their breaths, and as he calmed down, he started to realize, that he just had an amazing orgasm after mind-blowing sex, which included him getting spanked, a vibrator in his ass and being completely dominated.

He wanted to be embarrassed but there was barely enough receptors working in his body right now, and he was so tired he was already falling asleep even before he could stop his erratic breathing, he was barely aware of Rin's arm sneaking around his waist, and a light breath beside his ear when he finally, fell asleep.   
\-----------------------------------

Rin blinked his eyes a couple of times, slowly rousing from slumber, it was nice to wake up slowly and quietly like this, without having the alarm to do that for you, he was warm and relaxed, he realized the reason for his contentment was a warm body, pressed against him, breathing deeply, black hair messy in the most beautiful way possible, he would never tell anyone just how gorgeous and beautiful he finds Haru when sleeping, even Haru himself.

He knew Haru wasn’t going to be exactly happy about last night, but he’ll deal with the consequences later.

It didn’t take him long to drift back to blissful sleep.     


	2. Fanart

**Summary for the Chapter:**

> Sorry if you thought there will be a new chpter.  
> This is baiscally a Fanart i drew for this fic, because why not ..

 

[Click here to go to image](https://rinharu4everblog.tumblr.com/image/173303416676)

Follow this link to see the photo, if it didn't work, please copy/paste (https://rinharu4everblog.tumblr.com/image/173303416676) in the URL box.  
Thank you for taking the time to see this ...

**Author's Note:**

> Opinions are appreciated ...  
> P.S the kiss on the nose is totally Yohao's fault.


End file.
